1. Field of the Invention
This invention relates to sealant compositions and more particularly relates to hot melt sealants based on crosslinked butyl rubber.
2. Description of the Prior Art
It is known that sealant compositions can be used in various automotive and construction applications as barriers to prevent the passage of water, moisture, air, gases, dirt, dust, etc., from one surface to another. Most known sealants have some effectiveness in this regard, but some - notably the butyl sealants - have better barrier properties than the others.
A disadvantage of known butyl sealants is that they are not particularly effective in imparting structural strength to the adhering substrates, and structural stength must therefore be provided by appropriate design and engineering of the components. The bond strength can be improved by using a hot melt sealant instead of the conventional sealants that are applied at room temperature, but even the hot melt sealants of the prior art do not have sufficient strength to impart structural and dimensional strength to sibstrates combined therewith.